forster



. FO'RSTER.

OIL TANK.

Patented Nov. 22

(No Model.)

Illlllllllllllllilllllll 5 WISSES ATT RNEYS...

UNITED STATES PATENT OFFICE.

FRANK N. FORSTER, ()F BUFFALO, NEW YORK.

OIL-TANK.

SPECIFICATION forming part of Letters Patent No. 249,918, dated November 22, 188i. Application filed March 10, 1881. (No model.)

To all whom it may concern:

Be it known that I, FRANK N. FORSTER, of Buffalo, in the county of Erie and State ofNew York,have invented a new and useful Improvement in Oil-Tanks, of which the following is a specification. I,

The object of my invention is to provide certain new and useful improvements in tanks for storing petroleum, whereby the tanks will be protected from the effects of lightning.

In the accompanying drawings, Figure 1 is a plan view of an oil-tank provided with my improvements. Fig. 2 is a longitudinal section elevation of the same on the line 00 ac, Fig. 1. Fig. 3 is a cross-sectional elevation ofthe same on the line y 3 Fig. l.

Similar letters of ret'el ence indicate corresponding parts. i

The roofA of the oil-tank B is covered with tarred felt a, or paper, ,or some other material that will make it air-tight, so that none of the gases in the tank can escape through leaks in the roof.

The man-hole gate 0 has packing c to prevent the escape of gas. A pipe, D, is secured to the top of the tank, and this pipe is pro vided with a pressure-valve, E, that can only be opened by pressure of gas coming from the tank, and thus permit the gas to escape when there is an undue pressure in the tank, and this escaped gas can be conducted into a suitable receptacle. A pipe, F, also is connected to the top of the tank B, and this pipeis provided with a valve, G, which can only be opened by pressure of the air pressing into the tank. This valve is opened automatically as soonvas a vacuum is formed in the tank and admits air. A pipe, H, extends from the top of the tank down to within a few inches from the bottom of the same. The level of the oil will rise as high in this tube as in the other parts of the tank, and if a gage-rod, J, is placed into this tube H the height of the oil in the tank can be obtained without causing gas to escape, and without unscrewing or opening the top of the tank.

The inlet-pipe K of the tank B is connected with the ground by a suitable metal connection, L, a short distance from the tank, and between this ground-connection L and the tank B a piece, M, of pipe, of non-conducting or insulating material-such as rubber, glass, &c.- is introduced in the line of the pipe K.

For the purpose of connecting the ends of the pipe K, to which the insulating-pipe M is fastened, plates N are fastened to the ends of the pipe K, and these plates are connected by a series of rods, 0 0. These rods are insulated from one of the plates N by washers P,of rubber or other insulatingmaterial.

The collars Q Q for holding the insulating pipe M in place are screwed into recesses in the plates N N as shown in Figs. land 2. The inlet-pipe K enters the tank B at the bottom and extends up to the top of the same on the inside, as shown, or it enters the tank on the top. The outlet-pipe R is also provided with an insulated section and with a groundconnection, in the same manner as the inletpipe.

It is well known that a rising quantity of gases attracts lightning, and I have therefore taken all possible precaution to prevent such escape of gases from the oil-tank by means of the devices described. It considerable quantitles of gas accumulate in the tank and the pressure increases, the valve E is opened by the pressure, and the gases are conducted to places some distance from the tank. If this gas should become ignited, the valve E prevents any return of the flames into the tank. The valve Gr admits air when the tank is being emptied, so

as to prevent a vacuum being formed in the tank. The level of the oil can be ascertained very conveniently and without permitting any of the gas to escape. lt'a current ofelectricity passes along the pipe K, it will pass through the ground-line L into the earth and cannot harm the tank or its contents. The currentcannot pass through pipeM, as this is made of nonconducting material, and cannot pass through the rods 0 O,which arcinsulated by the washers P, made of non-conducting material.

Having thus fully described niy invention, lei-aim as new and desire to secure by Letters Patent- The combination, with the inlet and outlet pipes of an oil-tank, of insulating-pipes M, plates N, rods 0, connecting the plates, said rods being insulated at one end, and groundrod L, substantially as described, whereby the tank is insulated from the said inlet and outlet pipes, as set forth.

I FRANK NEWTON FORSTER. Witnesses: A. J. HAWKS, T. J ONES. 

